Findings of the Diabetes Control and Complications Trial have resulted in children with diabetes receiving more intensive treatment than in past years: more frequent daily injections or pump therapy and more frequent blood glucose monitoring. These changes in treatment increase both the importance of family members in facilitating diabetes management and the impact of the disease on family life. Research has shown that parent and "family" involvement are crucial for improved adherence and glycemic control and that family communication and conflict predict adjustment to diabetes as well as adherence and control. Yet with very few exceptions, research on "family" factors has examined the role of parents or of general family functioning. While siblings represent a fundamental component of family life, very little research has addressed the role of siblings in pediatric diabetes treatment. The proposed study will examine siblings' role in the diabetes self-management of children and adolescents with diabetes in 150 families. Interview and questionnaire methodology will be used to assess sibling support of diabetes self-management according to child, sibling, and parent perceptions. Data will be analyzed in order to identify how sibling support of diabetes self-management and sibling relationship qualities are associated with quality of life, adherence, and glycemic control of the child with diabetes. A model of sibling caretaking will lay the groundwork for developing more potent family-based interventions that mobilize the resources of the whole family. The demands of diabetes and its treatment exert significant stress on the lives of the over 100,000 pediatric patients with the disease and their families. Although siblings' contribution to diabetes self-management has not been studied, their roles are likely to be significant. Thus, an understanding of sibling roles and responses and their relations to child health and quality of life is critical to developing more efficacious family-based and social network-based interventions for this population. [unreadable] [unreadable] [unreadable]